FIG. 1 is a partial cross-sectional view 100 of a prior art outer Christmas tree fastener 110, 111, 111A, 111B inserted into an outer back 106 in proximity with an aperture 102 in an inner back 101. Foam 103 is placed over inner back 101. Typically, inner back 101 is made of wood or it may be plastic in some instances. A covering 104, for example, which may be leather or some other material, is placed over foam 103 and is stapled 105 to the wood substrate 101 as shown. Stapling wraps the covering around the foam and secures the foam in place. Christmas tree fastener 110, 111 is typically made of plastic and includes a shank portion 111, 111A as illustrated in FIG. 1F. Shank portion 111, 111A is illustrated in FIG. 1 as being aligned with aperture or bore 102 in inner back 101. As used herein the terms “bore” and “through-bore” are used interchangeably.
Head 110 of the Christmas tree abuts the exterior surface of outer back 106. Outer back 106 may be masonite, stiff cardboard or thin plywood. The outer back may be 0.125 inches thick by way of example. Other thicknesses and materials may be used for the outer back. Shank 111, 111A is press fit into bore 106A of outer back 106. Bore 106A is formed by drilling as described below. Foam 107 or other padding covers outer back 106 and a leather cover 108 is wrapped over the foam 107 and stapled 109 as illustrated to form a surface which appears to be homogeneous. Shank 111, 111A has a diameter which is larger than the through bore 106A and is thus formed therein and retained by the deformation of the Christmas tree branches 111, 111A.
FIG. 1F is a perspective view 100F of the prior art Christmas tree fastener of FIGS. 1-1E illustrating branches 111, 111A of the Christmas tree alternately and orthogonally arranged with respect to each other. As the branches 111, 111A are inserted into through-bore 102 they are deformed. In fact, branches 111, 111A are deformed as they are inserted into through-bore 106A. Reference numeral 111B is used to denote a knob on the end of the Christmas tree fastener.
FIG. 1A is a cross-sectional view 100A of the prior art outer Christmas tree fastener inserted into an outer back 106 which in turn has been inserted into the inner back 101 joining the inner 101 and outer backs 106 together. Branches 111, 111A of the Christmas tree fastener are bent as they are forced into a smaller diameter through-bore 102 of the inner back 101. A small gap exists between the outer surface 120 of the of the inner back 101 and the inner surface 120A of the outer back 106 caused by the build up of the thicknesses of the covers 104, 108.
FIG. 1B is a cross-sectional view 100B of the prior art Christmas tree fastener in an arrangement similar to that illustrated in FIG. 1 with the outer back 106 and the inner back 101 positioned in proximity to each other and with the inner back 101 having an aperture or through bore 102B which is not coaxial (not aligned) with the aperture or through bore 106A inserted into the outer back 106.
Further, branches 111, 111A of the Christmas tree fastener can be thought of as forming a cylindrically-shaped outer surface which is to be inserted into a cylindrical through-bore 102B. FIG. 1C is a cross-sectional view 100C of the prior art Christmas tree fastener similar to the view of FIG. 1B with the Christmas tree fastener partially inserted in the inner back 101 and broken as indicated by reference numeral 111C. Stress buildup is caused within the plastic Christmas tree fastener as the shank 111, 11A is pushed and shoved into receiving bore 102B which is not aligned with bore 106A of the outer back 106.
The contoured inner and outer backs typically made of wood are used in furniture construction. The contours make drilling of through-bores in the inner and outer backs difficult. During the furniture manufacture and assembly process the contoured inner and outer backs are processed so as to include bores or through bores as they are sometimes referred to herein. The bores are processed in one of three fashions, to wit: (1) the material is put into a press and the holes are punched out in the wood, masonite or cardboard; (2) the inner back may be made out of plastic and the holes are molded during the molding process; and, (3) the plywood inner backs or masonite outer back are drilled in multiple headed drilling equipment. All of these processes produce bores or through bores as they are called which are perpendicular to the work surface of the machine processing the component. This causes holes that are not perpendicular to the point the hole (bore) is produced since the seats have multiple compound curves in them. This induces failure in the prior art Christmas tree Easterners as described herein. As such, alignment of the through bores is not always achieved creating a need for a fastener system which is capable of tolerating alignment faults. When through bores are drilled in the inner backs, they are drilled on a machine surface. The operator of the drill does not always drill the through holes perpendicular to the surface of the wood. Rather, the operator tends to drill through-bores perpendicular to the machine surface and not perpendicular to the surface of a piece of wood.
The wood pieces (back) may be at an angle with respect to the drilling machine surface at the time the through-bore is drilled. If the operator drills through the piece of wood perpendicular to the machine surface then the through-hole is not perpendicular to a line tangent to the surface of the piece of wood being drilled.
In the furniture manufacturing assembly process the misalignment of the through bores in the outer and inner backs is a known problem which creates difficulties in the assembly of the outer back and the inner back together. If the Christmas tree connector of the prior art breaks as illustrated and described herein then the cover (which may be leather) must be removed along with the foam to access the area of the outer back in the vicinity of the broken Christmas tree connector. Staples are then used to join the outer back 106 and the inner back 101 together. If the covering is leather or some other soft material, however, then the staples used to join the outer and the inner backs together tends to tear the leather or any other soft covering which may be used.
FIG. 1D is a plan view 100D of the prior art Christmas tree fastener of FIGS. 1-1C.
FIG. 1E is a shank end view of the prior art Christmas tree fastener of FIGS. 1-1C.
U.S. Pat. No. 5,152,582 to Magnuson entitled Self-Aligning Fastener System Having Stud-Engaging Resilient Legs discloses a fastener having male and female members (fasteners). Stud fasteners 26 have a first end 72 which engage threads of a T-nut 25. Second end 74 of the stud 26 is generally rippled and extends through center apertures 102 of female fastener 46, aperture 38 of seat shell 14, aperture 51 of washer 50 (or retainer) and between resilient legs 76, 78 of female fastener. The fastener system of the '582 patent provides for a female member which may be moved in two axial directions to accommodate insertion of the male member therein.
The structure of the instant invention and the advantages its provides will be readily apparent to a person of ordinary skill in the art when reference is made to the Summary Of The Invention, Brief Description of the Drawings, Description of the Invention and Claims which follow hereinbelow.